I second the IK Hammond. It really fills in the sound nicely. IK had some specials this year, so I’m loaded with a lot of stuff from them now, including Miroslav Philarmonic.
Midishaper is a stand-alone LFO that works with any knob that has a midi learn. You can choose from various waves (sin, etc) or make your own. I made a how-to on it: https://twitter.com/HomeStudioImpr1/status/1343451174628945920
I got EW Bosendorfer this year, and it’s really the best piano VST I’ve used. Closest to the grand pianos I’ve played.
As I mentioned in other posts, the HY sequencers, HY-RPE2 and HY-Seqcollection2, are great for keyboard lines or drum tracks. With the HY-Seqcollection2, you can set up a line using the random function, and have fun tweaking various knobs in real time such as the pitch or harmonizing knob or pattern length knob. For drums this can be pretty fun, and sounds great even if though it’s monophonic. You can also chain patterns easily. HY-RPE2 is multitrack, but it does take a little more time to wrap your head around it. If you start learning with HY-Seqcollection2, it’s easier to understand HY-RPE2.
For arpeggios I sometimes use Chutlu. Many VST’s also come with their own arpeggios and arpeggiated patches.
This year I subscribed to Roland Cloud, which includes tons of synths and some drum machines from several decades of Roland history, so there really isn’t a lack of VST’s for me anymore.
The Softube line can add warmth and lo-fi things up a bit for sounds that sound too clinical/cold/factory. They released a bass VST and synth VST this year.
I’m working on using the Octatrack sequencer as the brains of it all so there’s so much to learn/explore. There’s no GAS at the moment for me… I can do a lot more by learning how to use what I have than getting new gear, and there’s a lot to learn.